The U.S. Senate last week passed a bill that would cancel a planned 10.6 percent payment reduction to doctors performing work under the Medicare plan, despite a veto threat from President George Bush. But experts say the underlying problems pressuring the government to keep doctors' reimbursement levels under control have not been addressed, The New York Times reported Sunday.

"The physician payment mechanism is hands down the most broken part of Medicare," Gail Wilensky, former Medicare administrator, told the newspaper. "We desperately need a new way to reimburse doctors. I fear that the need for fundamental change will be kicked down the road once the latest crisis has passed."

Some are calling for a new system that wouldn't base reimbursement on the current, complex procedure-by-procedure level, but instead make bundled payments to groups of doctors.

But doctors' groups are reluctant to propose such changes because it would create winners and losers within their profession, the newspaper said.